Apparatus for manufacturing closures



Jan. 7, 1941.

J. J. WILLIAMS 2,227,524

APPARATUS FOR MANUFACTURING CLOSURES Filed Nov. 8, 1958 2 Sheets-Sheetl 2 1I lllllllllll ,l a 3 jgg.

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Patented Jan. 7, 1941 UNITED STATES APPARATUS FOR MANUFACTURING CLOSURES John J. Williams, Wheeling, W. Va., assigner to Hazel-Atlas Glass Company, Wheeling, W. Va., a corporation of West Virginia Application November 8, 1933, Serial No. 239,566

4 Claims.

The invention relates to an improved apparatus for manufacturing snap-on closures, particularly such closures in which the skirt is smooth throughout, and without the lugs, or the position of the lugs, being in view.

One of the objects of the invention is to provide a simple and efficient apparatus for manwiacturing closures of this type, at high speed.

Various other objects and advantages of the invention will be apparent to those skilled in the art, from the following detailed description, when taken in connection with the accompanying drawings, in which:

ligure l is a vertical sectional view of the cap blanlr.

Figure 2 is a similar View, after the blank skirt has been incurled. s

Figure 3 is a vertical sectional view of the apparatus for forming the closure; the die being shown in elevated position.

Figure Il is a similar View, but with the die in lowered position.

Figure 5 is a horizontal sectional view, taken on line 5--5 of Figure It.

Figure 6 is a top plan view of the closure.

Figure '7 is a vertical sectional View of the closure, mounted in sealing position on a glass container.

Figure 8 is an enlarged, fragmentary, sectional view of the closure and container, and more clearly showing the relation between the glass iinish and one of the incurled lugs on the closure; and

Figure 9 is a View similar to Figure 3, but the section through the closure being taken between the incurled lugs.

Referring to the drawings in more detail, and particularly to Figures 6 to 9, numeral 1 indicates the upper portion of a container, which may be a bottle, jar, tumbler, or other glass container. Numeral 2 refers to a continuous annular glass bead, at the mouth of the container. This bead, which is known as the glass finish, is preferably substantially semi-circular in cross-section, and the locking lugs of the closure are adapted to snap over the bead, in sealing the container, as will clearly appear hereinafter.

The closure, which is referred to generally by the numeral preferably has a flat top 4. and the top may be provided with an annular groove or channel 5.

The depending skirt of the closure is referred to by numeral 6. The lower portion of the skirt is curled inwardly and upwardly, and certain spaced portions of the incurled bead are flattened outwardly against the skirt, leaving spaced incurled sections 1, which constitute the lugs for snapping over the glass finish 2. It will be noted that the lugs 'l are of considerable length circum- 5 ferentially, and it will also be noted that the upper end of the incurled lug is spaced from the closure skirt, as indicated by numeral B. By reason of this space, the resiliency of the lugs is very considerably increased, whereby the closure will w fit containers in which the diameter of the finish varies within normal limits, and whereby the removal of the closure is greatly facilitated. lin the speciiic embodiment illustrated, there are three lugs, and each lug has a length which is roughly about one-ninth of the circumference of the closure.

The flattened portions of the incurled bead, hetween the lugs, are referred to by numeral t. The internal diameter of lthe flattened portion of the skirt is greater than the external diameter of the glass hnish, so that the hattened portions pass freely over the glass nnish. The cross-sectional shape of these attened portions, best shown in Figure 9, is of material importance. lt will be noted, by reference to Figures 8 and 9, that the lower portion of the skirt, at the flattened portions, turns inwardly on exactly the same curvature as the incurled lugs. This curved portion of the skirt is indicated by numeral l0, and from the lower end of this curved portion the flattened portion 9 extends vertically upwardly, with the upper edge portion turned outwardly and downwardly, as indicated by numeral ll.

By reason of the fact that the curvature of the portion I0 at the flattened portions is exactly the same as the curvature at the lugs, it follows that the lower edge of the skirt has the same curvature throughout, and hence neither the lugs o nor the position of the lugs are visible from the exterior.

A ring of sealing composition l2 is arranged inside the closure, between the annular groove 5 and the depending skirt 6.

In sealing the containers, the closure is placed loosely thereon, with the incurled lugs 'Iresting on the mouth of the containers. In order to seal the container it is only necessary to apply pressure to the top of the closure, whereupon the incurled lugs will snap over the continuous glass bead 2, thereby locking the closure in sealing 'position. By reason of the space provided between the free end of the ncurled lugs and the skirt of the closure, the lugs are more resilient and hence the closure is more easily applied and removed. Of course the skirt of the closure also springs to some extent. particularly when the closure is ap-,

plied to maximum diameter containers.

The improved apparatus for manufacturing the closure, will now be described, reference being had particularly to Figures 1 to 5.

The blank shown in Figure 1, and referred to by numeral I3, is formed by a cut and draw die; and the edge of the blank skirt is then curled inwardly, as indicated by numeral I4, by means of a lcurling die. The cut and draw die and the curling die are not illustrated, as they form no part of the present invention.

Numeral I5 refers to a supporting plug, and numeral I6 refers to a locating ring slidably mounted on the plug, and normally held in its elevated position by springs I1. When the ring is in its elevated position it assists in properly positioning the closure blank on the supporting plug, and when the expanding die mechanism descends to form the closure it pushes the ring downwardly. 'I'he blanks with the incurled bead I4 may be delivered to the supporting plug I5 by hand or by any suitable feed mechanism.

Numeral I8 refers to the die holder which is clamped or otherwise secured to the crosshead of a press. Slidably mounted in the die holder is an ejector pad I9, which is normally maintained in elevated position relative to the di holder, by a coil spring 20.

A centering ring 2| is mounted on the lower end of the die holder, and this ring is preferably beveled as indicated by numeral 22. Above the beveled portion the ring is cylindrical to conform to the cylindrical blank skirt. Above the cylindrical portion the centering ring curves inwardly a short distance, as indicated by numeral 23, and this curvature is the same as the curvature of the incurled bead I4. This curved portion 23 of the ring is in contact with the incurled bead, when the expanding die comes into action, and thus the exterior curvature of the lower edge of the closure is maintained uniform throughout.

The expanding die segments, three in number, are referred to by numeral 24, and these segments are mounted for sliding lateral movement, between the holder I8 and ring 2|; the segments being maintained in proper circumferential position, and normally urged inward, by spring 25.

'Ihe segments 24 have conical surfaces cooperating with conical ejector pad I2, so that when the segments move downward relative to the pad, they are forced outwardly to pinch or flatten the incurled bead I4 at the desired points. The outer face of each expanding die segment has a cylindrical portion 26 which comes into contact with the incurled bead I4 in the flattening operation. And the outer face of each of these segments also has cut-away portions 21, and these portions are cut back far enough to prevent contact between them and the incurled bead, so that the bead retains its original form at these points. These portions of the incurled bead which retain their original shape, constitute the locking lugs 1 of the closure.

In operation, blanks with the incurled bead I4 are delivered to the supporting plug I5 by any desired means, and are properly positioned thereon by the locating ring I6. The expanding die holder now descends bringing the pad I9 into contact with the bottom of the closure blank and firmly holding it in position during the forming operation.

In this downward movement of the die holder, the centering ring 2l engages the locating ring I B and moves it downwardly, whileV the cylindrical portion of the centering ring passes over the blank skirt.

After the pad I9 contacts with -the bottom of the blank, it cannot move further downward, but the die holder and associated parts continue their downward movement. This slight further downward movement brings the curved portion 23 of the centering ring into contact with the exterior curved edge of the bead I4, preventing any deformation of the exterior curvature of the bead; and at the same time the expanding die segments are moved outwardly, thereby flattening the bead I4 where the cylindrical surfaces 26 of the segments contact with the bead, to form the flattened portions 9 of the closure. The cut-out portions 21 of the expanding die segments do not contact with the incurled bead, and these undeformed portions of the bead constitute the locking lugs 1 of the closure. Thus the closure is completed in one stroke of the die.

The die holder and associated parts now move upwardly, carrying the completed closure in the centering ring. As the die holder approaches its upper limit of travel the stem of the ejector pad strikes an arm (not shown), which prevents further upward movement of the pad. The other parts continue their upward movement, causing a relative downward movement of the ejector pad to forcibly eject the completed closure. The closures fall by gravity, or may be blown by compressed air, into a container suitably placed to receive them.

As previously mentioned herein, the snap-on closure disclosed herein possesses numerous advantages over prior closures of this type. It presents an unusually attractive appearance, by reason of the fact that the skirt is smooth throughout, and with neither the lugs nor the position of the lugs being in view. Also, the closure is very strong, produces an eilcient seal, and may be easily removed when the container is to be opened. Further, the construction of the closure is such that it may be manufactured at a high rate of speed by the apparatus disclosed herein, requiring only a single stroke of a die to complete the closure, from a blank having an incurled bead.

No claim is made herein to the closure; such claims being made in my divisional application Serial Number 275,299, filed May 23, 1939.

Having fully described the invention, what I claim is:

1. Apparatus for forming metallic closures with snap-on lugs, including a plug to receive a blank having a skirt with an incurled bead, a die holder, a ring carried by the die holder, said ring having a cylindrical portion corresponding with the blank skirt, and also having an incurved portion above the cylindrical portion and corresponding with the cross-sectional curvature of the blank where the bead joins the skirt, a plurality of expanding die segments carried by the die holder, the die segments having smooth wide external operating faces curved to substantially the curvature of the closure skirt, said operating faces being circumferentially spaced apart where the lugs are to be positioned where- F by the incurled bead remains undeformed at said spaced points, and means for moving the segments outwardly to flatten circumferentially spaced portions of the incurled bead.

2. Apparatus for forming metallic closures with lll] snap-on lugs. including a plug to receive a blank having a skirt with an incurled bead, a vertically movable locating ring siidably mounted on said plug, a die holder, a centering ring carried by the die holder, said centering ring having a cylindrical portion corresponding with the blank skirt, and also having an incurled portion above the cylindrical y,portion and corresponding with the cross-sectional curvature of the blank where the bead joins the skirt, a plurality of expanding die segments carried by the die holder, thehdie segments having smooth wide external operating faces curved to substantially the curvature of the closure skirt, said operating faces being circumferentially spaced apart where the lugs are to be positioned whereby the incurled bead remains undeformed at said spaced points, means for moving the segments outwardly to natten circumferentiaily spaced portions of the incurled bead, and springs normally maintaining the segments in their inward positions.

3. Apparatus for forming metallic closures with snap-on lugs, including a plug to receive a blank having a skirt with an incurled bead, a vertically movable locating ring slidably mounted on said plug, a die holder, a centering ring carried by the die holder, said centering ring upon downward movement adapted to engage and move downward the locating ring, said centering ring having a cylindrical portion corresponding with the blank skirt, a corneal ejector pad carried by the die holder and adapted to engage the blank on the plug, a plurality of expanding die Athroughout the circumference of the blank, ex-

segments carried by the die holder. the die segments having smooth wide external operating faces curved to substantially the curvature of the closure skirt, said operating faces being circumferentiaily spaced apart where the lugs are 5 to be positioned whereby the incurled bead. remains undeformed at said spaced points, said segments having inner faces cooperating with the conical ejector pad, springs maintaining the y segments in operative relation with the conical ejector pad, and said segments when moved outwardly engaging and nattening circumferentiaily spaced portions of the incurled bead.

4. Apparatus for forming metallic closures with snap-on lugs, including a plus to receive a blank having a skirt with an incurled bead, a die holder, means carried by the holder for engaging and maintaining the cross-sectional curvature of the blank where the bead joins thev skirt,

panding die segments carried by the die holder. the die segments having smooth wide external operating faces curved to substantially the curvature of the closure skirt, said operating faces being circumferentially spaced apart where the lugs are to be positioned whereby the incurled bead remains undeiorxned at said spaced points, and an injector pad, said pad having downwardly flared sides for moving the segments outwardly to engage and flatten circumferentially spaced so portions of the incurled bead.

JOHN J. WILLIAMS. 

